下向分层充填法中的人工假顶视为简支梁，当超过充填体强度时假顶会出现裂缝，存在冒顶危险；探地雷达是一种有效的无损探测手段。首先研究了单一均匀胶结尾砂充填体介质中裂缝正演特征，其次分析了多层介质中裂缝正演特征，并将2种正演特征进行对比，最后研究了室内胶结尾砂充填体模型中的垂直雷达响应特征，室内模型探测结果为沿垂直方向一系列的绕射双曲线。研究结果表明：探地雷达能够探测胶结尾砂充填体中的裂缝，为现场裂缝探测提供判读依据。%The stability of artificial roof in downward cemented cut and fill mining is analyzed by using simply supported beam theory. Cracks will appear when the strength of the filling body exceeds its ultimate strength. Then the artificial roof is in danger of roof falling. Ground penetrating radar (GPR) is an effective means of non-destructive detection. Firstly, characteristics of cracks in single uniform medium are studied by the forward modeling. Secondly, characteristics of cracks in multilateral medium are analyzed, and the two kinds of forward feature are compared. Finally, characteristic of responses of a vertical crack contained in cemented tailings backfill model in the laboratory are studied to find out a group of hyperbolic waves along the vertical direction. The study shows that the cracks in artificial roof of cemented tailings backfill can be detected by GPR and it provides a basis for interpretation in field detection.
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